docs: def _format_with_same_year_and_month(format_specifier):
      """
      Return a version of `format_specifier` that renders a date
      assuming it has the same year and month as another date. Usually this 
      means ommitting the year and month.
  
      This can be overridden by specifying a format that has 
      `_SAME_YEAR_SAME_MONTH` appended to the name in the project's `formats` 
      spec.
      """
      test_format_specifier = format_specifier + "_SAME_YEAR_SAME_MONTH"
      test_format = get_format(test_format_specifier, use_l10n=True)
      if test_format == test_format_specifier:
          # this format string didn't resolve to anything and may be a raw format.
          # Use a regex to remove year and month markers instead.
          no_year = re.sub(YEAR_RE, '', get_format(format_specifier))
          return re.sub(MONTH_RE, '', no_year)
      else:
          return test_format